Comments on: Higgs in Space!

By: Robert Frost

Robert Frost — Fri, 04 Dec 2009 04:04:20 +0000

WIMPS observed in nature =0
WIMPS observed in “papers” = 1,323,183,220,140,264*

A commanding lead!

*(seems to roughly obey Benford’s law)

By: Aaron Sheldon

Aaron Sheldon — Thu, 03 Dec 2009 17:20:44 +0000

Thanks Tim,

The paper is definitely closer to the line of logic I was considering.

By: Tim Tait

Tim Tait — Thu, 03 Dec 2009 04:44:53 +0000

Aaron,

This is not exactly what you are asking, but there was a recent paper which put limits on the elastic scattering cross section of WIMPs such that they do not exchange so much energy that elliptical galaxies collapse into spherical structures:
http://arXiv.org/abs/0911.0422
That seems to be closer to your original question than the worry that WIMPs will annihilate into light particles, which will escape and the galaxies will ‘evaporate’, which is what would happen if annihilation rates were large.

The above paper claims to put bounds which are on the order of 0.1 GeV^-2 on the elastic cross section. This is more than a million times larger than a typical WIMP annihilation cross section
(as inferred, say, by the relic density).

By: Aaron Sheldon

Aaron Sheldon — Wed, 02 Dec 2009 19:16:29 +0000

Can you put some specific limits on what is “not nearly fast enough” from the stability of galaxies and clusters, and then work out how much excess radiation we should expect to see?

By: Sean

Sean — Wed, 02 Dec 2009 18:24:10 +0000

Aaron, generally it’s a matter of numbers; the dark matter can lose energy, but not nearly fast enough to affect its dynamics in a galaxy or cluster.

By: Aaron Sheldon

Aaron Sheldon — Wed, 02 Dec 2009 17:29:54 +0000

How do you re-heat the dark matter to keep it from collapsing, if there is any process by which dark matter can loose energy?

By: Cartesian

Cartesian — Wed, 02 Dec 2009 16:48:30 +0000

And about the boson show?

By: Cartesian

Cartesian — Wed, 02 Dec 2009 10:33:55 +0000

I did try arxiv but I am not from a university, so it is not possible for me to publish there.

By: Alexander Fry

Alexander Fry — Wed, 02 Dec 2009 09:52:37 +0000

They state that this is the "perfect mass range for searches with the Fermi LAT". Testable predictions are good, but their final statement is dreamy, "As we explore the weak scale, we expect the dynamics of the electroweak breaking to be revealed. It may be that its secrets already shine down from the sky, produced by dark matter annihilation." And of course there is Bowie in Space.

By: Tim Tait

Tim Tait — Wed, 02 Dec 2009 06:18:53 +0000

Hi Sean,

Thanks for the “award”!

In a recent talk at Davis ( http://hep.ps.uci.edu/~tait/talks/Davis-WIMP%20Forest.pdf page 37 or so) Max Chertok anticipated the Muppet connection about 5 slides before I got to it… I had underestimated how strong the association is, I guess…

By: Aaron Bergman

Aaron Bergman — Wed, 02 Dec 2009 03:46:43 +0000

And here I thought it was referring to this.